CN1168231C - Noise suppression method and apparatus for enhanced wireless data network telephony - Google Patents

Abstract

A data network telephony system (99) includes a router (410) coupled to a DNT-capable data network (500), and a wireless transceiver (400). The base station is configured to operate the transceiver (400) via a bi-directional, narrowband, multi-channel, real-time duplex radio protocol. A plurality of portable computer-enhanced communication devices (100, 200, 300, and 600) each for communicating with a router (410) over the two-way, real-time duplex radio protocol and handling DNT calls include microphone and speaker means (105 and 106).

Description

Noise suppression method and device for enhanced wireless data network phone

technical field

The present invention relates to the field of network communication, including data network telephony (DNT) such as Internet Protocol Network Telephony (IPNT), in particular to a method and device for enhancing DNT on narrowband wireless links.

Background technique

Advances in telephony technology have been driven in part by improved telephony infrastructure, equipment, and methods of implementation. Traditional and legacy telephony communications have been practiced through the use of networks that provide dedicated connections and guaranteed bandwidth, such as the Public Switched Telephone Network (PSTN). In this type of network, a call from a phone connected to a local service is switched to the destination through a dedicated channel, and the dedicated path with dedicated bandwidth is maintained as long as the connection is maintained. Such networks may technically be referred to as connection-oriented switched telephony (COST) networks, and this term is also used in this specification.

More recently, with the development of extended data networks, of which the well-known Internet is a prime example, newer forms of telephone communication have been introduced. This form of telephony is referred to herein as Data Network Telephony (DNT), which belongs to Internet Protocol Telephony (IPNT) of the Internet data network. Data networks typically connect computers of one or more subnetworks, which may include local area networks (LANs), wide area networks such as the Internet, corporate intranets, and combinations of these and other data networks.

In DNT such as IPNT, dedicated connections are provided only in rare and special cases. Instead, digital audio data is prepared in standardized audio packets with header information and the like. These packets are prepared in near real time and propagated across the data network connection involved computers suitable for DNT applications. The header of each packet includes the packet's destination address.

Data network telephony such as IPNT is well known to those skilled in the art, and wireless data transmission is quite well known in many applications. For example, Internet service providers are recently offering high-speed wireless Internet access via satellite systems with essentially unlimited bandwidth at the receiver, and these systems have proven successful for WEB page delivery and the like. These systems have not proven friendly for DNT applications, and there are a number of reasons that would affect such systems as well as other types of more bandwidth-limited wireless systems.

The problem with telephony over data networks in wireless systems is related to the real-time nature of telephony data in these systems and the often limited bandwidth available. In a relatively wider bandwidth system with a relatively large number of users, the distribution probability satisfies the situation that there are usually no cases where some or more users request abnormal bandwidth at the same time, a phenomenon known in the art as equal distribution. Even at so-called peak times, bandwidth can be expected to be sufficient with this allocation. In most wireless systems, however, bandwidth is at a premium, so an even distribution is not that useful.

The nature of real-time audio data presents a delivery problem, as opposed to data transfer storage files and the like, and transfers of data storage files may be referred to as data-to-data transfers (as opposed to voice-to-data). Data - Data is prepared in packets to transfer a known amount of stored data. The number of packets required to transfer a stored file, which may be text, image, audio, or other type of file, is known. Also, if this data is delayed in transit, there is no major loss. Once the data reaches its destination, the file can be regenerated.

The voice-data packets used for real-time conversations are different. Voice-data packets must be prepared and transmitted in real time in both directions, otherwise a meaningful session cannot be maintained. In addition, the packet voice-data size of a session can be inflated by acoustic background noise, in some cases by double, triple, or even more than the amount of data to be sent, which imposes higher demands on the available bandwidth. requirements.

Contents of the invention

The present invention has carefully considered various types of potential DNT application possibilities and has determined that it is anticipated that DNT can be provided in various wireless systems to take advantage of some of the inherent advantages of DNT over dedicated connection type telephone systems, as well as to provide DNT applications The system can also transfer the above-mentioned data-data types, such as stored data files and entities. The new system proposed in this patent application has DNT capability and communicates using a relatively small, battery-powered, handheld computer that the user can carry within range of multiple network interface adapters (satellite transceivers). In a preferred embodiment, wireless communication is provided by RF signaling. However, the present invention is not limited to RF, but may be implemented in infrared systems or any other system that provides wireless communication.

In such a system, the network interface adapter can be coupled, eg, to a local area network. Such a system is particularly useful for employees on an enterprise basis to keep in touch, conduct telephone conversations, share local (campus network) files, and communicate with the Internet and other connected computers (or campus Internet or extranet). Various modifications are possible to such a system, but the art does not consider such a system to be practical. The methods and apparatus according to various embodiments and aspects of the present invention described in detail below provide substantial improvements and are believed to be quite feasible and useful for such voice/data systems over narrowband links.

According to an aspect of the present invention, a kind of data network telephony (DNT) system comprises:

a base station connected to a DNT-capable data network and a wireless transceiver operating the transceiver via a two-way, narrowband, multi-channel, real-time duplex radio protocol; and

a plurality of portable computer-enhanced communication devices, including a microphone and speaker arrangement, each communication device communicating with a base station via the two-way, real-time radio protocol, and handling DNT calls;

at least one digital signal processor (DSP) for recognizing human speech in each communication device;

wherein the base station is also used to process DNT calls over a DNT-capable data network, and to send and receive DNT calls in the form of DNT data packets via transceivers to and from a plurality of communication devices, and the communication devices only respond to the DSP identification human speech to generate data packets for transmission.

According to another aspect of the present invention, there is provided a microphone and speaker assembly for generating a noise suppression zone for use in a portable computer enhanced communication device in a Data Network Telephone (DNT) network, the apparatus comprising:

A main microphone and loudspeaker for voice transmission in the DNT system;

at least one auxiliary microphone;

at least one auxiliary speaker;

Wherein the auxiliary microphone intercepts the background noise, and reproduces the background noise to one or more auxiliary speakers which are precisely arranged, so as to remove the background noise within the range of the main microphone.

According to another aspect of the present invention, a method for converting bandwidth is provided, comprising steps:

(a) monitor the audio input in each communication device by the speech recognition DSP in the communication device;

(b) Only in response to voice input recognized by the DSP, data packets are prepared to be transmitted by the corresponding communication device.

In addition, the present invention provides a method for permanently generating a noise suppression zone in a portable computer-enhanced communication device, wherein the communication device is used in a data network telephony (DNT) system, the method comprising the steps of:

(a) positioning the primary microphone of the portable computer enhanced communications device at the first location;

(b) providing an auxiliary microphone at the second location;

(c) an auxiliary loudspeaker in the third position;

(d) Use the auxiliary microphone to intercept the background noise, and broadcast the intercepted background noise through the auxiliary speaker, so as to remove the background noise in the middle area of the main microphone.

In a preferred embodiment of the present invention, a data network telephony (DNT) system is provided that includes a base station connected to a DNT-capable data network and a wireless transceiver, and connected via a two-way, A narrowband, multi-channel, real-time duplex wireless protocol is suitable for operating the transceiver. The system also includes a plurality of portable computer-enhanced communication devices including microphone and speaker units, both adapted to communicate with the base station via the two-way real-time wireless protocol, and adapted to handle DNT calls. The base station is also adapted to handle DNT calls on a DNT-capable data network, and bi-directionally broadcast and receive DNT calls, such as DNT data packets, with a plurality of communication devices via a transceiver. In one embodiment, the DNT-capable network is a local area network (LAN).

In a preferred embodiment, one or more communication devices are equipped with a digital signal processor (DSP) for recognizing human speech, and the audio data for a DNT call is processed by the DSP, allowing only human speech to be transmitted as DNT packets.

In another instance, noise suppression associated with one or more communication devices equipped with a noise canceling microphone and speaker arrangement can create a noise suppression zone in the area of the primary speech input microphone. The present invention provides a method for a system providing wireless communication over a dedicated channel between a portable communication device adapted for data network telephony and a base station. A method for minimizing data traffic on a channel, comprising the steps of: (a) receiving speech at a microphone of a portable communication device; (b) by a digital signal processor (DSP) system for distinguishing human speech from background noise processing the speech; and (c) preparing and transmitting data packets derived only from the speech. In the method of some embodiments, the DSP functionality is provided by a dedicated chip or chipset coupled to the internal bus of the portable device. In other embodiments, the DSP functionality is provided by the CPU of the portable communication device.

In another aspect of the present invention, a wireless communication system has a base station connected to a transmitter/receiver (transceiver) by a hard-wired link, wherein the total wireless bandwidth is allocated for each user by a channel, in this A method is provided in the system to ensure shared bandwidth between users, the method comprising the steps of: (a) reflecting channel assignments for wireless communication to users on the hardwire link, thereby creating a virtual channel on the hardwire link; and (b) According to the virtual channel applied on the hardwire link, Granville Wireless transmits the data designated by a specific channel to the transceiver.

The unique nature of wireless communications of the present invention provides the advantages of real-time data network packet telephony in an extremely narrowband system and extends this telephony technology to the field of hand-held, portable communication devices.

Description of drawings

FIG. 1 is an overview diagram of the structure of a wireless DNT system according to an embodiment of the present invention.

Figure 2 is a system block diagram of components and component connectivity within a handheld DNT device and associated network elements according to one embodiment of the present invention.

Fig. 3 A is a DSP functional block diagram illustrating an embodiment of the present invention;

Figure 3B is a perspective view of the unit 100 of Figure 1 showing the speaker and microphone layout;

FIG. 4 is a conceptual diagram illustrating QoS components and protocols according to one embodiment of the present invention;

FIG. 5 is a block diagram illustrating dynamic address translation according to one embodiment of the present invention.

Detailed ways

FIG. 1 is an overview diagram of the structure of a wireless DNT voice-to-data system 99 according to one embodiment of the present invention. The wireless voice-data system 99 includes a plurality of receiving and transmitting handheld devices 100-600 that may be carried and used by individuals to move within a local area such as a corporate campus having multiple buildings or the like. System 99 is in various embodiments a communication system based on radio frequency (RF) technology, which may be a time division multiple access (TDMA) system, a code division multiple access (CDMA) system, or any other type of two-way wireless protocol system, All of these systems are technically public or can be invented in the future, but they are basically wireless systems.

In other embodiments, voice/data 99 may operate via infrared or other known or future forms of wireless communication. Radio frequency systems are used for illustration in this embodiment because of their flexibility and wide technical application. In some cases, a combination of wireless technologies can be used, such as combining the performance of infrared technology with radio frequency technology. The infrared characteristics are caused by the peripheral equipment used in the system.

Each handheld device 100-600 (or more or less) is a portable computer or computing device such as a palmtop. This apparatus is known in the art and is suitable for the practice of the invention, with certain additional elements, as will be described in detail below. Each receiving/transmitting device communicates via RF as previously described and has an RF interface such as an interface module 109 capable of receiving and transmitting radio signals and having network interface capabilities.

Each device 100-600 has some computer functionality derived from palmtops and other portable computers and, in most embodiments, is powered by rechargeable batteries. In some embodiments where portability is not an issue, they can also be powered via a wall outlet so that the battery pack can be recharged. However, in a preferred embodiment, device 100 is portable. It will be apparent to those skilled in the art that voice/data system 99 may be used with as many other devices as the available bandwidth allows.

Each device 100-600 is capable of communicating in RF mode with a satellite transceiver 400, which may be located within the total proximity (communication range) of portable devices within the subnet system 99. The satellite transceiver 400 is dedicated to transmit and receive data bi-directionally between each device such as devices 100-600 in RF mode, and has interface capabilities suitable for computer communication, and radio frequency transmission and reception capabilities. The satellite transceiver 400 is linked via a dedicated digital connection 401 to a router 410 shown in this embodiment. There are various forms of this link, such as serial pair, optical link, etc.

More specifically, router 410 is a digital routing node for routing data packets in a data network such as the Internet. However, in some specialized embodiments where calls are received from a telephone network such as the Public Switched Telephone Network (PSTN), or from a digital network, routers containing both types of telephony capabilities may be used. The present invention contemplates dual capable routers (ie, routing PSTN calls converted to DNT calls as well as the original source DNT calls).

Router 410 is linked to a network 500 via a digital network connection. Network 500 may be in the form of a local area network (LAN), a wide area network (WAN), the Internet, the Internet, or other types of public or private digital networks known in the art. Router 410 may be further linked to other routers or transceivers (not shown) via dedicated connections 411 and 412 as shown, which may occur in a multi-distributed system in which a voice/data system such as system 99 Replicated and distributed within a larger geographic area (eg, a campus), and linked into a network such as network 500 . Dedicated connections 411 and 412 are both within the scope of connection 410 as previously described.

In an exemplary system according to the present invention, each transceiver, such as transceiver 400, communicates with users on 16 dedicated narrowband channels. In some cases, the transceiver area may have more than 16 devices 100-600 assigned to user and transceiver channels. In some cases, a channel can be shared by two or more infrequently used users, while frequently used users can have a dedicated channel. In the embodiment of the system 99 having multiple transceivers, a user equipped with a communication device roams between systems, as described in more detail below.

According to a preferred embodiment of the present invention, DNT such as IPNT can be realized by the user operating a portable communication device such as device 100 while being connected in wireless mode to a voice/data system such as system 99, enabling the user to actively send and Receive real-time data related to DNT, and perform other data tasks, such as file downloads, uploads, and the like, without losing the quality of real-time DNT communications. Such a user may also roam away from or beyond the service area of the system 99 system 99, in a multi-distributed embodiment, wherein as the user moves between transceiver areas, any information sent but not received by him Real-time data is immediately rerouted because the user is being associated with a new satellite transceiver. This feature allows the user to move freely during real-time data transmission.

As described above with reference to the background section, DNT is not currently available when applied to networks with narrower dedicated bandwidths, such as TDMA or CDMA systems, compared to high-bandwidth systems (e.g., wireless satellite systems and connection-oriented systems). OK, where sufficient bandwidth to satisfy DNT and other data transmissions can be guaranteed by other technologies such as packet averaging technology. It is therefore an object of the present invention to provide methods and apparatus which enable DNT including IPNT to be successful and economically viable in the aforementioned prevalent existing narrowband type wireless networks. Such methods and apparatus of the present invention are described hereinafter by various embodiments.

FIG. 2 is a system block diagram of components and component connectivity within voice/data device 100 of FIG. 1 , and associated network elements external to device 100 according to one embodiment of the present invention. The voice/data handheld device 100 of FIG. 2 is shown as a block diagram to show various components and functions, some of which may implement the unique functions of the present invention, and some of which are standard functions available from the prior art and common to these devices.

Device 100 in this embodiment has a central processing unit (CPU) 101 comprising a digital signal processor (DSP) 101a. In some embodiments, DSP 101a may be separate from CPU 101, such as a separate chip that communicates on bus 113. DSP 101a is used for speech recognition, which can separate human speech from background noise. The DSP functionality provided in this embodiment is unique and will be described in further detail below.

Since the device 100 is a portable computer or a DNT communication device, it provides suitable memory for storing programs and data, such as memory (MEM) 102 and non-volatile memory (NV MEM) 103.

Voice system 104 contains the necessary components for DNT and IPNT telephony, as well as the necessary A/D and D/A conversion between digital voice-data and analog voice signals from a microphone (mic) or operating speaker. In this embodiment, microphone 106 and speaker 105 are used for audio transmission and reception. In some cases, an additional noise canceling microphone 106b and noise canceling speaker 105b may be included for reducing background noise. This noise canceling technique applied to an embodiment of the present invention will be described in detail below.

Infrared transceiver 107 is used to interface with peripherals that communicate via infrared signals. Infrared transceiver 107 accepts input from such peripherals and converts this data to digital form for bus 113 . Of course, other forms of wired (such as USB) or wireless desktop networks are also applicable, including but not limited to inductive, RF, etc. Data mentioned in the background section - data, such as files and the like, can be converted to infrared data, stored, executed or printed on an infrared capable peripheral that may be used on system 99.

Like most portable computers, device 100 is provided with a standard keyboard 112 and screen 110 . The screen can be various devices known in the art, and the keyboard can be a QWERTY keyboard or other types. In some embodiments, a miniature keyboard 111 is also used in the device 100 instead of the keyboard 112 for the purpose of inputting the operation of the device 100, such as simulating a simple telephone interface. Similarly, as peripherals such as full-size keyboard 151, PC 152 may communicate with device 100 via the aforementioned infrared or other wired or wireless links. RF interface 109 provides a digital wireless interface with transceiver 400 .

Obviously, for those skilled in the art, there may be some common or new functions inherent or known in the present invention that are not described in detail in this embodiment for palmtop or laptop computers. The purpose of the present invention is only to be described in detail in connection with the device 100 in relation to the operation of the present invention. Common components such as screen 110 and keyboard 112 are not described in detail, as doing so would obscure the innovative aspects of the present invention. The innovative viewpoints according to the embodiments of the present invention will be described in detail below.

Improved Noise Suppression for DNT Applications

In an embodiment of the present invention, satellite transceivers 400 in the system of FIG. 2 (additional such transceivers may be connected to router 410, or an equivalent router) are typically within a specified frequency range surrounding the transceiver area. Signals are transmitted on a fixed number of channels within the network. Typically, each handset is tuned to a specific channel, which may be negotiated with a router 410 or other intelligent device in the system. Thus, the number of users in such systems within the range of a satellite is usually relatively small, and each user communicates with router 410 via transceiver 400 over a "thin pipe". In this specification, by thin pipe is meant a connection to the user via a very bandwidth-constrained channel.

As is apparent from the present invention, the main problem with implementing DNT on such narrow-band thin pipes is noise rejection. As previously described in the background section, background noise severely limits the available bandwidth because packets are prepared essentially in real time, even during long pauses in a session, packets must be prepared for background noise. Thus wasting bandwidth that could be more beneficially used for other purposes, such as exchanging data-to-data, or relying on the wireless network to share with other users. The present invention proposes two schemes, which can be used alone or in combination, greatly reduce the waste of bandwidth due to background noise, and are used for DNT communication on narrowband pipelines.

The first implementation involves the use of a DSP with speech recognition capabilities (see DSP 101a in Figure 2), as will be described and illustrated below.

Figure 3A is a block diagram illustrating a DSP in accordance with one embodiment of the present invention wherein only voice data packets and actual data packets are sent during a transaction with a calling or called party.

DSP technology, while well known in the art and used in many different types of products, is a novel solution when applied to one embodiment of the present invention. The inventors are aware of no narrowband wireless applications currently using a DSP with voice recognition capability for bandwidth management, whereby only necessary voice-data packets are created during real-time transactions such as DNT voice calls. Data related to file transfers and other similar transfers - The data is created in the usual way and sent along with the voice data. In some cases, the CPU can be used to perform DSP tasks, so there does not necessarily need to be an external physical implementation of the DSP. Also, some newer DSP designs will help to handle general-purpose CPU/MPU functions, thus being able to handle all cases by themselves.

Referring now to FIG. 3A, when the user speaks into the microphone during a call, the DSP 101a with speech recognition capability monitors the input, selects speech from non-speech, creates data packets for speech only, and does not create packets during periods when the user is not speaking. In this way, bandwidth is available for other functions, since data packets containing background noise and the like are not built up. Data-data packets containing non-voice data, such as file transfer data and the like, are created in the usual way and sent with the DNT packet, if of course the user is transferring a file and talking on the device at the same time. In this embodiment, this technique assumes that there is sufficient bandwidth for multitasking functions while actively engaging in DNT calls.

The speech recognition function of the DSP chip can be programmed or linked to recognize different languages. Sighs and other verbal non-descriptive words can be ignored during the monitoring and DNT packet generation process.

In another embodiment of the present invention, a DSP chip with voice recognition capability may also be provided in a router such as router 410 . By using digital-to-analog conversion modules well known in the art, incoming DNT packets can be monitored by a similar DSP at router 410 prior to rounds, and non-speech packets can be purged from the received DNT data stream. The DSP devices and techniques described above are effective in minimizing the bandwidth requirements of the DNT on one-way or two-way narrow wireless channels.

FIG. 3B is a perspective view of the device 100 of FIG. 1 showing the combination of a noise canceling speaker and microphone. While a DSP with speech recognition capability can effectively reduce unwanted background noise, it is not 100 percent effective, so another noise suppression technique is used, in which a second microphone 106b and more than one speaker 105b may be provided, and there is Purposefully placed on device 100 for the purpose of reducing background noise that may be present at the user's location. The additional MIC/SPKR may or may not be required, depending on the implementation and physical design of the device. If a system such as system 99 of FIG. 1 is implemented in an industrial environment, for example, where background noise is particularly severe, then microphone 106 and speaker 105 are used for normal voice and audio functions during DNT calls, or may be combined for noise cancellation.

It will be apparent to those skilled in the art that more than one noise canceling speaker 105b, and more than one noise canceling microphone 106b may be present in device 100 without departing from the spirit and scope of the present invention. The number and location of such devices will depend in part on the purpose of the application. For example, in a quiet environment, no noise canceling device of any kind is needed, whereas in a noisy environment, maximum noise canceling capability needs to be provided. Generally, the noise canceling system works by cutting off the background noise by the auxiliary microphone (106b), which is then played back by placing one or more noise canceling speakers to cancel the background noise in the area of the main microphone 106. The effect of such noise cancellation on e.g. traffic noise and similar noises is well known in the art, but the application of background noise suppression and techniques to achieve enhanced DNT transmission over narrow wireless links is unique and less obvious.

It will be apparent to those skilled in the art that the noise canceling speaker and microphone can be separated from the device 100 without departing from the spirit and scope of the present invention. One such example is the use of noise canceling headphones.

Pipe Mirroring in Narrowband Wireless Multiple Access Systems

Attention is now drawn to hardwired link 401 between intelligent router 410 and transceiver 400 in FIG. 2 . Router 410 is used to route packet data for voice-data in DNT and data-data such as file transfers to users within the coverage area of transceiver 400 . Typically each user is assigned to a channel within range of the transceiver, so that each user's voice-data and data-data occupies only the one channel on the wireless link between the transceiver 400 and each user's handheld device. channel. Hardwire link 401 is preferably a wire that carries all combined data for all users within transceiver area 400 . However, this scheme invites trouble because router 410 only sees the combined bandwidth of all channels. Thus, when one or more users choose to download large amounts of data, router 410 will typically command the entire bandwidth of hardwired link 401 to transmit the data to transceiver 400, thus potentially interrupting some or all DNT communications. In a preferred embodiment of the present invention, router 410 treats hardwired link 401 as if it were a link in the wireless channel bandwidth for each user, dividing the wireless link into a number equal to the number of wireless channels used parallel pipeline. Real-time voice-to-data and data-to-data data management can thus be maintained between system routers and users, and DNT communications can be efficiently maintained for individual users.

QoS functions on ultra-thin pipes

In a preferred embodiment of the present invention, to ensure that when a combination of DNT data and application data is sent for each client through the narrowband wireless channel, the DNT data takes precedence, a basic but innovative QoS scheme is implemented at the client side.

Those skilled in the art know that traditional two-way QoS application schemes, such as Resource Reservation Protocol (RSVP) and similar schemes, are only used for high bandwidth applications, where many users share the available channels. It is also well known that QoS guarantees at both ends of the pipe must be negotiated along the node-to-node direction. Moreover, it is difficult to realize QoS through multiple networks. Therefore some operations need to be standardized so that all network points understand and support the language protocol of the scheme used.

FIG. 4 is a conceptual block diagram illustrating QoS management according to an embodiment of the present invention.

The inventor's goal is to provide a new, unilateral QoS implementation from the client side to the other end of the pipe (ie router 410). This is accomplished in embodiments of the invention either by firmware embedded into NVMEM 103, or by a software application 501 installed in available system memory of device 100. In this embodiment, an instance of application 501 also resides in router 410 . This application provides a fixed algorithm that is always preferred to process DNT data in the device 100 and router 410 . In this way, DNT data always guarantees sufficient bandwidth as real-time data. If another data type such as data from a file transfer is initiated while a DNT call is in progress, then all these packets are blocked until there is a pause in the speech and no DNT data is being transferred. File transfers initiated by device 100 only occur during data breaks in prioritized DNT communications. This is a unidirectional feature, affecting only the communication link between device 100 and router 410, with instances of application 501 operating independently at each end. In another embodiment, this unique unidirectional QoS process is only used at one end or the other end of the pipe, ie either at the router 410, or in the user's handheld device.

Dynamic Address Translation

In another embodiment of the present invention, a method is provided by which a user can roam away from or out of range of a transceiver such as transceiver 400 and log into the system 99 smoothly and efficiently. other transceivers.

FIG. 5 is a block diagram illustrating dynamic address translation according to one embodiment of the present invention. Transceivers 97, 98 and 99 are three separate but overlapping transceivers, such radio systems are known in the art, eg found in cellular telephone systems. Areas 97 , 98 and 99 together define subnetwork 404 . Subnet 404 is in this case served by a single router 410 . This situation could represent, for example, a technology park. Each device 100 can handle one or the other defined channel in each zone 97-99, and RF tuning in handheld devices is a matter of equipment and procedures, as is known in the art.

Router 410 in this embodiment is a lower-level router in a multi-level routing system connected to a higher-level router 415 via link 413 . In this embodiment, router 415 is the main router of the wireless system and is linked to network 500 . Master router 415 may also be linked to other lower level routers, such as router 417 in another subnet 405 equivalent to subnet 404 , which in turn may control three transceivers, such as transceiver 418 .

It will be apparent to those skilled in the art that various configurations can be implemented, including various levels of routers, interconnections between routers, and connections from routers to transceivers, to achieve coverage of the area of such a wireless communication system. The structure illustrated here is one of many possibilities and is used as an example for the purpose of illustrating improved performance in tracking users across subnets of an embodiment of the present invention.

In general, when incoming DNT calls arrive at the main router 415, they are routed appropriately based on routing tables in several routers. Throughout the system, each user has a primary address served by a particular transceiver connected to a particular router, for example, a particular user can usually be found in the area 99 served by transceiver 403 connected to router 410. This user will be listed in the routing table of the router 410 and the routing table of the main router 415. If the call of this particular user comes to the main router 415, the call can be quickly routed to the correct router end and send and receive through the routing table entry. machine. Each satellite transceiver, such as transceiver 403, has a fixed number of channels, and each user is assigned a channel.

The purpose of such a distributed system as illustrated in an embodiment of the present invention is to provide communication to all users regardless of a particular area (transceiver) and to allow users to move between areas while maintaining communication.

As an example, a user of device 100 shown in FIG. 5 is located in area 99 and decides to roam to area 97 covered by transceiver 402 . In the system of various embodiments, location negotiation occurs periodically with each device operating with the closest transceiver. As long as the user does not move from one area to another, the routing table does not change. When a user of device 100 enters area 97, transceivers 403 and 402 may communicate for negotiation. At some point, the system will determine that the user will be handed over to transceiver 402, at which point the routing table is updated, removing that particular user from transceiver 403, and assigning the user to transceiver 402.

Each handset tunes to a channel assigned by the system and device 100 will begin negotiating with router 410 via transceiver 402 on the same channel assigned to devices in area 99 served by transceiver 403 . However, one or more users in area 97 are assigned to the same channel, and once this routing table is modified, the channel assignment will also change at the newly entered area. Each transceiver has, for example, more channel capacity than expected users in that area at any one time, and thus may have unused channels at any point in time that may be allocated to new users entering that particular area.

In this example, router 410 serves both areas 99 and 97 via transceivers 403 and 402, making this a relatively simple example of Ripple. However, if the user of device 100 roams to subnet 405, where the transceiver is controlled by router 417, then device 100 will connect to this new router through the nearest satellite transceiver and negotiate entry to the new subnet. In this case, the user would move from the routing table of router 410 to the routing table of router 417, rather than just modifying the routing table in router 410 to a new transceiver and area.

In Ripple's process, users are tracked throughout the area covered by the wireless system and their locations relative to network transceivers are annotated. As users move between areas in the manner described above, the routing tables in each router are updated with minimal impact on the system's storage and modification of data, with minimal changes to the routing tables.

When a user moves from one area to another as described above, and the routing table is modified, there will be situations where the user is receiving real-time data packets as DNT while the user's location is being modified. When a user is relisted to a new area, there may be data packets sent to the routers that the user previously listed. At this instant, the live data packet, or any data packet delayed in this way for that matter, is held and forwarded immediately to the router serving the area to which the user has moved, so there is no noticeable effect on the data flow for the roaming user. Loss.

It will be apparent to those skilled in the art that variations in the number of routers are possible, such as router 410 assigning different numbers of satellite transceivers, without departing from the spirit and scope of the invention. In more complex systems, there may be several layers of hierarchical routers, and the possibilities for system structure are varied.

Client's Personal Router

In yet another embodiment of the present invention, a software application called the Personal Router Application by the inventors may be used to increase routing flexibility. A detailed description of such a personal router system is found in patent application 08/xxx,yyy, which is assigned as assignee for the present patent application and is hereby incorporated by reference in its entirety.

In the personal router system, a user, through an executable application on the handheld device, can program other actions on incoming calls. For example, a user may need to leave an area and a collaborator is selected to cover the first user's area of responsibility. In this case, the first user can program through the handheld device and the personal router application that incoming calls to the first user are rerouted to another option. A wide range of options are available, including auto-answer with pre-recorded messages, call hold, and many other methods. In a preferred embodiment, a user interface is provided wherein an incoming call is represented by an icon on the user's screen and the user can choose to dispose of the call.

In one embodiment, most of the personal router applications are located on the system router, and each user has an interface through which the user can access the application on the system router in a client-server manner, and edit the routing rules on the router, To influence how users handle incoming calls. The rules that can be used in this manner are limited only by the capabilities of the system and the needs of the user.

The personal router application provides the user with maximum flexibility without requiring additional equipment. Users do not have to be on either voice/data system in order to apply their own personal routing rules. By having a router application instance for each router in the network, users can roam without losing the ability to access individual routers. By using router hierarchies, individual routing capabilities can be increased to cover larger geographic areas, such as routing calls to other subnets, and so on.

It is obvious to those skilled in the art that the personal routing application can be used in combination with other routing applications, and can be implemented separately in a single device without departing from the spirit and scope of the present invention. For example, as a DNT telephony application, routing software can be stored on a machine dedicated to connecting routers so that more complex routing rules can be found.

Realization of DNT Wireless Telephone on CSMA/CD Type Network

All of the foregoing embodiments of the invention are applicable to typical types of wireless network bandwidth allocated, such as TDMA and CDMA networks. However, the successful practice of the present invention in various embodiments can be further enhanced by implementing a wireless protocol between the transceiver and the user based on the characteristics of Carrier Sense and Multiple Access with Collision Detection (CSMA/CD). Much of this type of network often appears as a hardwired or wireless LAN structure, such as Ethernet.

In CSMA/CD, all data is transmitted on a shared channel, and every registered device attempting to transmit data on the network must first listen to see if the network is idle (carrier sense). Each device is preset to use the available bandwidth on the network with priority (multiple access). A collision occurs if two devices try to transmit at the same time, which is detected by all devices on the network (collision detection). Each device typically waits for a random amount of time after detecting a collision before scheduling its second transmission attempt. Since all of this happens on the microsecond scale, CSMA/CD provides a way to efficiently use the available bandwidth in a wireless sharing system.

Bandwidth-on-demand (Bandwidth-on-demand) means that no device can send while there are other devices on the network sending. Instead of a single channel of dedicated bandwidth allocated to each device, all incoming DNT communications travel through the entire network, where each device picks up its own encoded information by assigning addresses within packet frames.

The operation of CSMA/CD in the wireless mode is basically the same as that in the hard-wired mode, except that the network structure is tighter than that of the wired network in terms of linking devices. The inventors are aware of no wireless CSMA/CD network currently capable of implementing DNT. To implement the present invention, the wireless CSMA/CD can use existing wireless LAN technology by replacing an RF/NIA adapter such as module 109 in FIG. 1 with an existing LAN type network adapter.

It is obvious to those skilled in the art that the method and device of the present invention described by the various embodiments provided allow DNT including IPNT to be cost-effectively implemented on a wireless narrowband network with a dedicated channel, and when there is a network with carrier detection Listening and collision detection capabilities can be cost-effectively implemented on a shared channel wireless network without departing from the spirit and scope of the present invention. For example, the current methods and apparatus can be used in various networks such as TDMA, CDMA, Global System for Mobile Communications (GSM), and other similar networks and CSMA/CD type networks.

Equally, it will be obvious to those skilled in the art that the wireless network enhanced by the method and device of the present invention may comprise multiple voice/data systems belonging to one of multiple subnets, each subnet controlled by a router, each Routers are connected to LANs and WANs, including but not limited to the Internet. The spirit and scope of the present invention are limited only by the appended claims.

Claims (2)

1. a data network telephony (DNT) system comprises:

Base station, described base station are connected to data network and the radio receiving-transmitting unit with DNT ability, and by two-way a, arrowband, the described transceiver of duplex wireless electricity protocol operation in real time;

A plurality of portable computer enhanced communications equipment, it comprises microphone and speaker unit, each described communication equipment by should be two-way, electric agreement of real-time radio and described base station communication, and processing DNT calling;

At least one digital signal processor (DSP) is used for discerning the human speech of each described communication equipment;

Wherein said base station also is used for handling DNT and calls out on the data network with DNT ability, and the DNT that sends and receive with DNT packet form by the round a plurality of described communication equipments of described transceiver calls out, and described communication equipment only in response to the human speech of DSP identification, generates the packet that is used to transmit.

2. according to the DNT system of claim 1, the data network that wherein has the DNT ability is a Local Area Network.

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